The main goal of the proposed research is to provide a more complete assessment of hearing in the Belgian Waterslager canary. This strain of canary has a hereditary hearing loss associated with missing and damaged hair cells. Little is known about how these hair cell abnormalities affect hearing, other than elevating pure tone thresholds, particularly at high frequencies. In the present study, psychoacoustic methods will be used to investigate hearing abilities in Belgian Waterslager and normal hearing canaries. In a series of behavioral experiments, I will assess frequency analysis, temporal processing, and perception of vocalizations. The performance of Belgian Waterslager canaries on these tasks will be compared to the performance of normal hearing canaries. In addition, I will investigate the behavioral effects of hair cell damage and regeneration after noise exposure in these birds, followed by an anatomical study of the basilar papillae. What makes canaries especially interesting subjects for hearing experiments is that they have been used in many behavioral and neurobiological studies of vocal learning and neurogenesis. Thus, the proposed experiments will increase our understanding of the functional consequences of hearing impairment in these birds, and of hearing impairment in general.